Foreclosure starts jumped by double digits from July to August in four out of five Western states tracked by ForeclosureRadar, reversing what had been a declining trend over the past several months, the company said.

The increase in foreclosure starts seen in Arizona, California, Nevada, Oregon and Washington appeared to be driven primarily by Bank of America and related companies, which boosted notice of default and notice of trustee sale filings by 116 percent from July to August.

Wells Fargo and US Bank also ramped up foreclosure start filings, ForeclosureRadar said, while filings by JP Morgan Chase and Citibank were essentially flat, ForeclosureRadar said.

In California, foreclosure starts jumped nearly 70 percent from July to August, totaling 31,965 — the highest level in a year. The average time to foreclose in California increased to 333 days in August, 49 days longer than a year ago.

Notice of trustee sale filings were up more moderately, rising 6 percent from July to August but still down nearly 24 percent from a year ago at 24,020.